1. Field of the Invention
The present disclosure relates to a scroll compressor having a bearing, and more particularly, to a scroll compressor having a bearing which is interposed between a rotational shaft of the scroll compressor and an orbiting scroll to reduce friction loss.
2. Background of the Invention
A scroll compressor is a compressor which includes a fixed scroll having a fixed wrap and an orbiting scroll having an orbiting wrap engaged with the fixed wrap, in which as the orbiting scroll makes an orbiting movement on the fixed scroll, a compression chamber formed between the fixed wrap and the orbiting wrap is continuously changed to thus suck and compress a refrigerant.
A scroll compressor continuously performs sucking, compressing, and discharging, and thus, it is superior to other compressors in terms of vibration and noise generated during an operation process.
Behavior characteristics of a scroll compressor are determined by the configuration of the fixed wrap and the orbiting wrap. The fixed wrap and the orbiting wrap may have a certain shape, respectively, but in general, the fixed wrap and the orbiting wrap have a form of an easily processable involute curve. In the case of using an involute curve, a thickness of the wraps is uniform and a rate of change in volume according to a rotation angle of the orbiting scroll is also uniform, and thus, in order to obtain a sufficient degree of compression ratio, the number of windings of the wraps should be increased. In this case, however, a size of the compressor is also increased as the number of windings of the wraps is increased.
Meanwhile, the orbiting scroll includes a disk having a disk-like shape and the foregoing orbiting wrap formed at one side of the disk. A boss portion is formed in a rear surface on which the orbiting wrap is not formed, to connect the orbiting scroll to a rotational shaft rotationally driving the orbiting scroll. This configuration is advantageous in that the orbiting wrap is formed over the substantially entire area of the disk, and thus, a diameter of the disk for obtaining the same compression ratio can be reduced, but disadvantageous in that a point of application to which repulsive power of a refrigerant and a point of application to which reaction force is applied to cancel out the repulsive power in the event of compression are separated from one another in a vertical direction, to cause the orbiting scroll to be inclined during an operation, increasing vibrations and noise.
As a solution, a scroll compressor in which a rotational shaft and an orbiting scroll are coupled in a surface on which an orbiting wrap is formed has been presented. In this compressor, a point of application of repulsive power of a refrigerant and a point of application of reaction force thereof are applied to the same point, solving the problem in which the orbiting scroll is inclined.
However, in the case in which the rotational shaft extends to the orbiting wrap portion, a central point of the orbiting scroll cannot be utilized as a compression space, and thus, in order to obtain the same level of compression ratio as that of the related art compressor, sizes of the orbiting scroll and the fixed scroll should be increased. This disadvantageously leads to an increase in a size and weight of the compressor.
The above references are incorporated by reference herein where appropriate for appropriate teachings of additional or alternative details, features and/or technical background.